Eventually Mark and his friends find a
vital codename and date, which they know they must solve in order to prevent
an imminent terrorist attack:

Nigel Argall has
worked with young people for twenty years. He lives in Southampton with his
wife Helen and four children, and is a self-confessed 'aviation nut' who helps
as a volunteer for the Air Training Corps. He loves writing but would rather
be outdoors – especially doing water sports.